Liquid Crystal Display and Display

ABSTRACT

A hand-held electronic device includes a liquid crystal display device having a first substrate, a second substrate bonded to the first substrate, with liquid crystal material held between the first substrate and the second substrate, and an upper polarizing plate affixed to the second substrate. A protective member is disposed over the upper polarizing plate, and an adhesive member is disposed between the protective member and the upper polarizing plate without an air layer between the protective member and the upper polarizing plate. The protective member is configured as a protective cover of the hand-held electronic device.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.13/279,587, filed Oct. 24, 2011, which is a continuation of U.S.application Ser. No. 12/437,218, filed May 7, 2009, now U.S. Pat. No.8,045,101, which is a continuation application of U.S. application Ser.No. 11/644,872, filed Dec. 26, 2006, now U.S. Pat. No. 7,532,274, thecontents of which are incorporated herein by reference.

CLAIM OF PRIORITY

The present application claims priority from Japanese Application JP2005-372185 filed on Dec. 26, 2005, the content of which is herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a liquid crystal display and a display.In particular, the present invention is concerned with a techniqueapplicable effectively to a liquid crystal display (module) used in ahand-held electronic device such as a mobile telephone terminal.

2. Description of the Related Art

A thin display such as a liquid crystal display has been conventionallyused for a display used in a hand-held electronic device such as amobile telephone terminal or a PDA (Personal Digital Assistant).

The liquid crystal display is a display having a liquid crystal displaypanel comprising a pair of substrates and a liquid crystal material heldtherebetween. One of the paired substrates is generally called a TFTsubstrate and, for example, comprises a glass substrate, as well as TFTs(Thin Film Transistor) and pixel electrodes formed on the substrate. Theother substrate is generally called a counter substrate and, forexample, comprises a glass substrate and a color filter, etc. formedthereon. In the case where the liquid crystal material driving method isa longitudinal electric field type, common electrodes (also calledcounter electrodes) opposed to the pixel electrodes are formed on thecounter substrate side. In the case where the liquid crystal materialdriving method is a lateral electric field type, the common electrodesare formed on the TFT substrate side.

With the recent tendency toward the reduction in thickness of thehand-held electronic device, the liquid crystal display used therein hasalso been becoming more and more thin. For example, as a method ofreducing the thickness of a liquid crystal panel, the method of reducingthe thickness of the liquid crystal display is known.

For example, a method of polishing the glass substrate used in the TFTsubstrate or the counter substrate is known as the method of reducingthe thickness of the liquid crystal display panel.

Also, as a method of reducing the thickness of a liquid crystal displaypanel, the method of using a plastic substrate for either one of the TFTsubstrate or the counter substrate instead of the glass substrate (see,for example, Japanese Patent Laid-Open No. 8-006039 (Patent Document 1))is known.

SUMMARY OF THE INVENTION

In the liquid crystal display, when the thickness of the glass substrateused in the TFT substrate or the counter substrate is reduced bypolishing in order to reduce the thickness of the liquid crystal displaypanel, the strength of the glass substrate is deteriorated and thestrength of the liquid crystal display panel is also deteriorated. Thus,the method of polishing the glass substrate to reduce the substratethickness poses the problem that it is difficult to attain boththickness reduction and ensuring of a sufficient strength.

Moreover, the method of using a plastic substrate instead of the glasssubstrate poses the problem that the heat resistance and solventresistance (chemicals resistance) of the plastic substrate are low incomparison with the glass substrate and that therefore the handling ofthe plastic substrate is difficult for example in the step of formingTFT onto the glass substrate. Further, in the case of a liquid crystaldisplay panel using a glass substrate as the TFT substrate and a plasticsubstrate as the counter substrate, unevenness in display easily occursbecause the substrates differ in the amount of deformation caused bychanges of environmental conditions such as temperature and humidity.

It is an object of the present invention to provide a technique able toattain both thickness reduction of a liquid crystal display panel andensuring of a sufficient strength of the panel.

It is another object of the present invention to provide a techniqueable to reduce the thickness of a hand-held electronic device such as aliquid crystal display (module).

The above and other objects and novel features of the present inventionwill become apparent from the following description and the accompanyingdrawings.

The following is an outline of typical modes of the present invention asdisclosed herein.

(1) A liquid crystal display comprising a liquid crystal display panel,the liquid crystal display panel having a first substrate, a secondsubstrate disposed on the side of an observer with respect to the firstsubstrate and opposed to the first substrate, a liquid crystal heldbetween the first substrate and the second substrate, an upperpolarizing plate disposed on the observer side with respect to thesecond substrate, and a resin film disposed on the observer side withrespect to the upper polarizing plate and affixed in contact with theupper polarizing plate, the resin film being higher in surface hardnessthan the upper polarizing plate.

(2) The liquid crystal display according to the above (1), wherein theresin film has a surface hardness of 3 H or harder in terms of surfacepencil hardness. (3) The liquid crystal display according to the above(1) or (2), wherein the resin film has a thickness of 0.2 mm or more.

(4) The liquid crystal display according to the above (1) or (2),wherein the resin film has a thickness of 0.2 mm or more and 1 mm orless.

(5) The liquid crystal display according to any one of the above (1) to(4), wherein the material of the resin film is an acrylic resin or anepoxy resin.

(6) The liquid crystal display according to any one of the above (1) to(5), wherein the first substrate has a thickness of 0.5 mm or less.

(7) The liquid crystal display according to any one of the above (1) to(6), wherein the second substrate has a thickness of 0.5 mm or less.

(8) The liquid crystal display according to any one of the above (1) to(7), wherein the thickness of the first substrate and that of the secondsubstrate are almost equal to each other.

(9) The liquid crystal display according to any one of the above (1) to(7), wherein the thickness of the second substrate is smaller than thatof the first substrate.

(10) The liquid crystal display according to any one of the above (1) to(7), wherein the thickness of the second substrate is larger than thatof the first substrate.

(11) The liquid crystal display according to any one of the above (1) to(10), wherein the total thickness of the liquid crystal display panel is2 mm or less.

(12) The liquid crystal display according to any one of the above (1) to(11), further comprising an upper phase difference plate disposedbetween the upper polarizing plate and the second substrate.

(13) The liquid crystal display according to any one of the above (1) to(12), wherein when the liquid crystal display panel is viewed from afront side thereof, an outline of the resin film is smaller than that ofthe upper polarizing plate.

(14) The liquid crystal display according to any one of the above (1) to(12), wherein the liquid crystal display panel further comprises a lowerpolarizing plate disposed on a back surface side of the first substrate,and when the liquid crystal display panel is viewed from the front sidethereof, an outline of the resin film and that of the upper polarizingplate are smaller than an outline of the lower polarizing plate.

(15) The liquid crystal display according to the above (14), furthercomprising a lower phase difference plate disposed between the lowerpolarizing plate and the first substrate.

(16) The liquid crystal display according to any one of the above (1) to(15), wherein the first substrate and the second substrate are glasssubstrates.

(17) A liquid crystal display comprising a liquid crystal display panel,the liquid crystal display panel having a first substrate, a secondsubstrate disposed on an observer side with respect to the firstsubstrate and opposed to the first substrate, a liquid crystal heldbetween the first substrate and the second substrate, an upperpolarizing plate disposed on the observer side with respect to thesecond substrate, and a resin film disposed between the upper polarizingplate and the second substrate, the resin film having a thickness of 0.2mm or more, the upper polarizing plate having a surface hardness of 3 Hor harder in terms of surface pencil hardness.

(18) The liquid crystal display according to the above (17), wherein theresin film has a thickness of 1 mm or less.

(19) The liquid crystal display according to the above (17) or (18),wherein the thickness of the first substrate and that of the secondsubstrate are almost equal to each other.

(20) The liquid crystal display according to the above (17) or (18),wherein the thickness of the second substrate is smaller than that ofthe first substrate.

(21) The liquid crystal display according to the above (17) or (18),wherein the thickness of the second substrate is larger than that of thefirst substrate.

(22) The liquid crystal display according to any one of the above (17)to (21), further comprising an upper phase difference plate disposedbetween the upper polarizing plate and the second substrate.

(23) The liquid crystal display according to any one of the above (17)to (22), wherein when the liquid crystal display panel is viewed from afront side thereof, an outline of the upper polarizing plate is smallerthan that of the resin film.

(24) The liquid crystal display according to any one of the above (17)to (23), wherein the liquid crystal display panel further comprises alower polarizing plate disposed on a back surface side of the firstsubstrate, and when the liquid crystal display panel is viewed from thefront side thereof, an outline of the upper polarizing plate is smallerthan that of the lower polarizing plate.

(25) The liquid crystal display according to the above (24), whereinwhen the liquid crystal display panel is viewed from the front sidethereof, an outline of the resin film is smaller than that of the lowerpolarizing plate.

(26) The liquid crystal display according to the above (24), whereinwhen the liquid crystal display panel is viewed from the front sidethereof, an outline of the resin film is larger than that of the lowerpolarizing plate.

(27) The liquid crystal display according to any one of the above (24)to (26), further comprising a lower phase difference plate disposedbetween the lower polarizing plate and the first substrate.

(28) The liquid crystal display according to any one of the above (17)to (27), wherein the first substrate and the second substrate are glasssubstrates.

(29) A liquid crystal display comprising a liquid crystal display panel,the liquid crystal display panel having a first substrate, a secondsubstrate disposed on an observer side with respect to the firstsubstrate and opposed to the first substrate, a liquid crystal heldbetween the first substrate and the second substrate, an upperpolarizing plate disposed on the observer side with respect to thesecond substrate, a lower polarizing plate disposed on a back surfaceside of the first substrate, and a resin film affixed in contact with aback surface side of the lower polarizing plate, wherein the totalthickness of the first substrate and the second substrate is 0.5 mm orless.

(30) The liquid crystal display according to the above (29), wherein theresin film has a thickness of 0.1 mm or more and 0.3 mm or less.

(31) The liquid crystal display according to the above (29) or (30),wherein the thickness of the first substrate and that of the secondsubstrate are almost equal to each other.

(32) The liquid crystal display according to the above (29) or (30),wherein the thickness of the second substrate is smaller than that ofthe first substrate.

(33) The liquid crystal display according to the above (29) or (30),wherein the thickness of the second substrate is larger than that of thefirst substrate.

(34) The liquid crystal display according to any one of the above (29)to (33), wherein the first substrate and the second substrate are glasssubstrates.

(35) A liquid crystal display comprising a liquid crystal display panel,the liquid crystal display panel having a first substrate, a secondsubstrate disposed on an observer side with respect to the firstsubstrate and opposed to the first substrate, a liquid crystal heldbetween the first substrate and the second substrate, an upperpolarizing plate disposed on the observer side with respect to thesecond substrate, a lower polarizing plate disposed on a back surfaceside of the first substrate, and a resin film disposed between the lowerpolarizing plate and the first substrate, wherein the total thickness ofthe first substrate and the second substrate is 0.5 mm or less.

(36) The liquid crystal display according to the above (35), wherein theresin film has a thickness of 0.1 mm or more and 0.3 mm or less.

(37) The liquid crystal display according to the above (35) or (36),wherein the thickness of the first substrate and that of the secondsubstrate are almost equal to each other.

(38) The liquid crystal display according to the above (35) or (36),wherein the thickness of the second substrate is smaller than that ofthe first substrate.

(39) The liquid crystal display according to the above (35) or (36),wherein the thickness of the second substrate is larger than that of thefirst substrate.

(40) The liquid crystal display according to any of the above (35) to(39), wherein the first substrate and the second substrate are glasssubstrates.

(41) A display comprising a display panel, the display panel comprisinga first substrate, a second substrate disposed on an observer side withrespect to the first substrate and opposed to the first substrate, andan upper polarizing plate disposed on the observer side with respect tothe second substrate, wherein the first substrate and the secondsubstrate are glass substrates and there is provided a resin filmdisposed on the observer side with respect to the upper polarizing plateand affixed in contact with the upper polarizing plate, the resin filmhaving a surface hardness of 3 H or harder in terms of surface pencilhardness.

In connection with the liquid crystal display according to the presentinvention, in the liquid crystal display of the first invention (1), aresin film is affixed in contact with the upper polarizing plate of theliquid crystal display panel, the resin film having a surface hardnesshigher than that of the upper polarizing plate. In the liquid crystaldisplay panel having such a resin film, the resin film functions as areinforcing member, whereby the strength of the liquid crystal displaypanel is enhanced. Therefore, even if one or both of the first andsecond substrates are reduced in thickness, it is possible to ensure asufficient strength of the liquid crystal display panel. With the resinfilm having the surface pencil hardness of 3 H or harder, the liquidcrystal display panel becomes difficult to be damaged. Consequently,when the liquid crystal display (module) having this liquid crystaldisplay panel is installed into a mobile telephone terminal, aprotective cover for protecting the liquid crystal display panel is notnecessary to be attached to the outer surface of the mobile telephoneterminal. As a result, a display unit of the mobile telephone terminalcan be made thin.

It is preferable that the thickness of the resin film be, for example,0.2 mm or more and 1 mm or less. It is preferable that the resin film beformed of a material high in light transmittance, especially acolorless, transparent material. As an example of such a material thereis an acrylic resin or an epoxy resin. In the case of using an acrylicresin or an epoxy resin as the material of the resin film, the surfaceof the resin is subjected to a hard coating treatment so as to give asurface pencil hardness of 3 H or harder. The surface pencil hardness ismeant a hardness with which the material surface is damaged when a lineis drawn on the material surface with a pencil. That is, the surfacepencil hardness of 3 H means that the film surface gets not damaged whena line is drawn on the film surface with a pencil with a pencil hardnessof 3 H or softer.

It is preferable that the first and second substrates each have athickness of 0.5 mm or less. The thickness of the first substrate andthat of the second substrate may be almost equal to or different fromeach other. In particular, the second substrate with the resin filmaffixed thereto is reinforced by the resin film and therefore, even ifit is thinner than the first substrate, it is possible to ensure asufficient strength. For example, in the case where the liquid crystaldisplay panel is of a lateral electric field driving type called IPS (InPlane Switching), a conductor film for the prevention of electriccharging may be provided on the surface to which the upper polarizingplate is affixed. In this case, for example, it is impossible to reducethe thickness of the second substrate by polishing. Therefore, in thecase where the aforesaid conductor film is provided on the secondsubstrate, the first substrate is made thinner than the second substrateto reduce the thickness of the liquid crystal display panel. In thiscase, it is preferable that the thickness of the resin film, that of thefirst substrate and that of the second substrate be set so as to give aliquid crystal display panel thickness of 2 mm or less.

In such a liquid crystal display panel, it is preferable that an outlineof the resin film be smaller than that of the upper polarizing plate forexample when the panel is viewed from the front side thereof. Forexample, when the liquid crystal display having the liquid crystaldisplay panel is installed into a mobile telephone terminal, thereusually is formed a slight gap between the sheath of the mobiletelephone terminal and the liquid crystal display panel, and water getsinto the inside of the mobile telephone terminal from the outsidethrough the gap. In this case, the outline of the resin film is madesmaller than that of the upper polarizing plate, whereby the upperpolarizing plate and the sheath of the mobile telephone terminal can beaffixed together between the outer periphery of the resin film and thatof the upper polarizing plate using a pressure-sensitive adhesive or thelike to fill up the gap. In this way it is possible to prevent the entryof water into the inside of the sheath.

In such a liquid crystal panel, for example, the lower polarizing platemay be disposed on the back surface side of the first substrate. In thiscase, for example when the liquid crystal display panel is viewed fromthe front side, it is preferable that the outline of the resin film andthat of the upper polarizing plate be smaller than the outline of thelower polarizing plate.

In such a liquid crystal display panel, for example, an upper phasedifference plate may be disposed between the upper polarizing plate andthe second substrate. Likewise, a lower phase difference plate may bedisposed between the lower polarizing plate and the first substrate.

In such a liquid crystal display panel it is preferable that both firstand second substrates be glass substrates. Even in the case of usingglass substrates as the first and second substrates, it is possible toreduce the thickness of each glass substrate because a sufficientstrength can be ensured by the resin film. Thus, it is possible toattain both the reduction in thickness of the liquid crystal displaypanel and ensuring of a sufficient strength.

In connection with the liquid crystal display according to the presentinvention, in the liquid crystal display of the second invention (17),the resin film is disposed between the second substrate and the upperpolarizing plate of the liquid crystal display panel. Also in this caseit is preferable that the thickness of the resin film be, for example,0.2 mm or more and 1 mm or less. In such a liquid crystal display panel,since the upper polarizing plate is disposed most closely to theobserver, the surface pencil hardness of the resin film is not requiredto be 3 H or harder. Instead, in the liquid crystal display of thesecond invention it is preferable that the surface of the upperpolarizing plate be subjected to a hard coating treatment so as tobecome 3 H or harder in surface pencil hardness. With thisconfiguration, it is possible to obtain the same effect as in the liquidcrystal display (liquid crystal display panel) of the first invention.

Also in the liquid crystal display of the second invention, thethickness of the first substrate and that of the second substrate may bealmost equal to each other or either one of the first or secondsubstrates may be reduced in thickness.

Also in the liquid crystal display of the second invention it ispreferable that the outline of the resin film be smaller than that ofthe upper polarizing plate for example when the liquid crystal displaypanel is viewed from the front side thereof.

In the liquid crystal display of the second invention, for example, alower polarizing plate may be disposed on the back surface side of thefirst substrate. In this case, it is preferable that the outline of theresin film and that of the upper polarizing plate be smaller than theoutline of the lower polarizing plate for example when the liquidcrystal display panel is viewed from the front side thereof.

Moreover, in the liquid crystal display of the second invention, forexample, an upper phase difference plate may be disposed between theupper polarizing plate and the second substrate. Likewise, a lower phasedifference plate may be disposed between the lower polarizing plate andthe first substrate. The upper phase difference plate may be disposedbetween the second substrate and the resin film or may be disposedbetween the resin film and the upper polarizing plate.

Further, in the liquid crystal display of the second invention it ispreferable that both first and second substrates be glass substrates.Even in the case of using glass substrates as the first and secondsubstrates, the glass substrates can be made thin because a sufficientstrength can be ensured by the resin film. Thus, it is possible toattain both the reduction in thickness of the liquid crystal displaypanel and ensuring of a sufficient strength.

In connection with the liquid crystal display according to the presentinvention, in the liquid crystal display of the third invention (29), aresin film is affixed in contact with the back surface side of the lowerpolarizing plate of the liquid crystal display panel and the totalthickness of both first and second substrates is 0.5 mm or less. In sucha liquid crystal panel it is preferable that the thickness of the resinfilm be, for example, 0.1 mm or less and 0.3 mm or more. With such athickness, when a pressing force is applied to the liquid crystaldisplay panel from the upper polarizing plate side, the resin film canbear the force, the resin film being affixed to the back surface side ofthe display panel. Thus, even if the first and second substrates aremade thin, it is possible to ensure a sufficient strength of the liquidcrystal display panel.

Also in the liquid crystal display of the third invention, the thicknessof the first substrate and that of the second substrate may be almostequal to each other, or either one of the first or second substrates maybe reduced in thickness.

Moreover, in the liquid crystal display of the third invention, it ispreferable that both first and second substrates be glass substrates.Even in the case of using glass substrates as the first and secondsubstrates, it is possible to reduce the thickness of each glasssubstrate because a sufficient strength can be ensured by the resinfilm. Thus, it is possible to attain both the reduction in thickness ofthe liquid crystal display panel and ensuring of a sufficient strength.

In connection with the liquid crystal display according to the presentinvention, in the liquid crystal display of the fourth invention (35),the resin film is disposed between the first substrate and the lowerpolarizing plate of the liquid crystal display panel and the totalthickness of the first and second substrates is 0.5 mm or less. Also inthis case it is preferable that the thickness of the resin film be, forexample, 0.1 mm or more and 0.3 mm or less. According to thisconstruction, the same effect can be obtained as in the liquid crystaldisplay of the third invention.

Also in the liquid crystal display of the fourth invention, thethickness of the first substrate and that of the second substrate may bealmost equal to each other, or either one of the first or secondsubstrates may be reduced in thickness.

Moreover, in the liquid crystal display of the fourth invention it ispreferable that both first and second substrates be glass substrates.Even in the case of using glass substrates as the first and secondsubstrates it is possible to reduce the thickness of each glasssubstrate because a sufficient strength can be ensured by the resinfilm. Thus, it is possible to attain both thinning of the liquid crystaldisplay panel and ensuring of a sufficient strength.

In the case of installing the liquid crystal display of the third or thefourth invention into a mobile telephone terminal, it is preferable thata protective cover for protecting the liquid crystal display panel beaffixed to a sheath of the mobile telephone terminal as in theconventional liquid crystal display. However, in the liquid crystaldisplays of third and fourth inventions, the total thickness of thefirst and second substrates is not larger than 0.5 mm and the thicknessof the resin film is 0.1 mm or more and 0.3 mm or less. That is, in eachof the liquid crystal displays of the third and fourth inventions, sincethe liquid crystal display panel is thinner than the conventional liquidcrystal display panel, the thickness of the liquid crystal display canbe so much reduced. Consequently, even if the protective cover forprotecting the liquid crystal display panel is affixed to the sheath ofthe mobile telephone terminal, it is possible to reduce the thickness ofthe display unit of the mobile telephone terminal in comparison with theconventional counterpart.

Although the first invention is concerned with a liquid crystal display,the same construction as the first invention is applicable to anydisplay insofar as the display has a liquid crystal panel of aconstruction similar to the construction of the liquid crystal displaypanel used in the liquid crystal display. For example, even in the caseof a display panel with a liquid crystal material not held between thefirst and second substrates, if an upper polarizing plate is disposed onthe observer side with respect to the second substrate, both thinning ofthe liquid crystal panel and ensuring of a sufficient strength can beattained by affixing the resin film in contact with the upper polarizingplate. In this connection, if the surface pencil hardness of the resinfilm is 3 H or harder, then as is the case with the liquid crystaldisplay of the first invention, for example when the liquid crystaldisplay in question is installed into a mobile telephone terminal, it isno longer required to use a liquid crystal display panel protectingcover and hence it is possible to reduce the thickness of the displayunit of the mobile telephone terminal. As an example of a display panelhaving a configuration similar to that of the liquid crystal displaypanel and not using any liquid crystal material, there is known aself-light emission type display panel using an organic EL.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view showing a schematic configuration of aliquid crystal display panel according to a first embodiment of thepresent invention;

FIG. 2 is a sectional view taken along the line A-A′ of FIG. 1;

FIGS. 3A and 3B are schematic sectional views for explaining a functionand effect of the liquid crystal display panel of the first embodiment;

FIG. 4 is a schematic front view showing a schematic configuration of adisplay unit of a conventional mobile telephone terminal;

FIG. 5 is a sectional view taken along the line B-B′ of FIG. 4;

FIG. 6 is a schematic front view showing a schematic configuration of adisplay unit of a mobile telephone terminal using the liquid crystaldisplay panel of the first embodiment;

FIG. 7 is a sectional view taken along the line C-C′ of FIG. 6;

FIGS. 8A and 8B are schematic sectional views showing modifiedconfigurations of the display unit of the mobile telephone terminalusing the liquid crystal display panel of the first embodiment;

FIG. 9 is a schematic front view for explaining an application exampleof the liquid crystal display panel of the first embodiment;

FIG. 10 is a sectional view taken along the line D-D′ of FIG. 9;

FIGS. 11A to 11C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel shown in FIGS. 9 and 10;

FIG. 12 is a schematic sectional view showing a schematic configurationof a liquid crystal display panel according to a second embodiment ofthe present invention;

FIGS. 13A to 13C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel of the second embodiment;

FIG. 14 is a schematic sectional view for explaining an applicationexample of the liquid crystal display panel of the second embodiment;

FIGS. 15A to 15C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel shown in FIG. 14;

FIG. 16 is a schematic sectional view showing a schematic configurationof a liquid crystal display panel according to a third embodiment of thepresent invention;

FIG. 17 is a schematic sectional view for explaining a modification ofthe liquid crystal display panel of the third embodiment;

FIG. 18 is a schematic sectional view showing a schematic configurationof a reflection type liquid crystal display panel to which the presentinvention is applied; and

FIG. 19 is a schematic sectional view showing a schematic configurationof an organic EL panel to which the present invention is applied.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention will be described in detail by way of embodimentsthereof and with reference to the accompanying drawings.

In all of the drawings for illustration of the embodiments, portionshaving the same functions are identified by the same reference numerals,and repeated explanations thereof will be omitted.

First Embodiment

FIG. 1 is a schematic plan view showing a schematic configuration of aliquid crystal display panel according to a first embodiment of thepresent invention, FIG. 2 is a sectional view taken along the line A-Aof FIG. 1, and FIG. 3 is a schematic sectional view for explaining afunction and effect of the liquid crystal display panel of the firstembodiment. In FIG. 3 there are shown two sectional views as FIG. 3A andFIG. 3B, both of which correspond to the sectional configuration takenalong the line A-A′ in FIG. 1.

In the first embodiment, a reference will be made to a transmission typeliquid crystal display as an example of a display to which the presentinvention is applied, and a description will be given below about theconfiguration, as well as function and effect, of a liquid crystaldisplay panel used in the transmission type liquid crystal display.

As shown in FIG. 1, the liquid crystal display panel of the firstembodiment includes a TFT substrate 1, a counter substrate 2, a liquidcrystal material 3 held between the TFT substrate 1 and the countersubstrate 2, a pair of polarizing plates 4, 5 disposed between the TFTsubstrate and the counter substrate 2 both holding the liquid crystalmaterial 3, and a resin film 6 affixed in contact with the polarizingplate 5 which is located on the counter substrate 2 side.

The TFT substrate 1 and the counter substrate 2 are bonded togetherthrough an annular sealing member 7 and the liquid crystal material 3 issealed and held within the space enclosed by the TFT substrate 1,counter substrate 2 and sealing member 7.

In the display having such a liquid crystal display panel, when seenfrom an observer side, the counter substrate 2 is usually disposed onthe observer side with respect to the TFT substrate. That is, when theliquid crystal display panel of the first embodiment is viewed from theobserver side, the resin film 6, polarizing plate 5, counter substrate2, liquid crystal material 3, TFT substrate 1 and polarizing plate 4 aredisposed in this order from the observer side. Therefore, in thefollowing description, the polarizing plate 5 disposed on the observerside (front side) with respect to the counter substrate 2 when seen fromthe observer side will be designated the upper polarizing plate, whilethe polarizing plate 4 disposed on the back surface side (back side) ofthe TFT substrate will be designated the lower polarizing plate.

The TFT substrate 1 includes a glass substrate 101 and a multi-thin filmlayer 102. Though detailed descriptions are omitted, the multi-thin filmlayer 102 is a laminate of plural insulating layers, conductive layer,semiconductor layer and the like. For example, a scanning signal line(also called a gate signal line), a video signal line (also called adrain signal line), TFT and pixel electrodes are formed in themulti-thin film layer 102.

The counter substrate 2 includes a glass substrate 201 and a multi-thinfilm layer 202. Though detailed descriptions are omitted, the multi-thinfilm layer 202 is a laminate of plural insulating layers and conductivelayer, forming a color filter for example.

In the case where the driving method for the liquid crystal displaypanel is of a longitudinal electric field type, common electrodes arealso formed in the multi-thin film layer 202 of the counter substrate 2and opposed to the pixel electrodes of the TFT substrate 1. Where thedriving method for the liquid crystal display panel is of a lateralelectric field type, the common electrodes are formed in the multi-thinfilm layer 102 of the TFT substrate 1.

Any of various combinations applied to conventional liquid crystaldisplay panels may be adopted for the combination of the configurationof the multi-thin film layer 102 of the TFT substrate and the multi-thinfilm layer 202 of the counter substrate 2. Therefore, detaileddescriptions on concrete structural examples of the multi-thin filmlayers 102 and 202 will be here omitted.

The lower polarizing plate 4 is affixed in contact with the glasssubstrate 101 in the TFT substrate 1 through a pressure-sensitiveadhesive for example. Likewise, the upper polarizing plate 5 is alsoaffixed in contact with the glass substrate 201 of the counter substrate2 through a pressure-sensitive adhesive for example. In this case, theupper polarizing plate 4 and the lower polarizing plate 5 are affixed tothe glass substrates in such a manner that their transmission axes (alsocalled polarization axes) intersect each other perpendicularly or areparallel to each other. For the lower polarizing plate 4 and the upperpolarizing plate 5, for example, film-like polarizing plates used inconventional liquid crystal display panels may be used. Detaileddescriptions on concrete structural examples of the material, etc. willbe here omitted.

In the liquid crystal display panel of the first embodiment, though notshown, a phase difference plate may be disposed between the glasssubstrate of the TFT substrate 1 and the lower polarizing plate 4 andalso between the glass substrate 201 of the counter substrate 2 and theupper polarizing plate 5.

The resin film 6 is a film member disposed on the most front side whenviewed from the observer side. Therefore, it is preferable that a filmwith a high light transmittance, especially a colorless, transparentfilm be used as the resin film 6. For example, an acrylic resin film oran epoxy resin film may be used as the resin film 6. The resin film 6 isaffixed in contact with the upper polarizing plate through apressure-sensitive adhesive for example.

In the liquid crystal display panel of the first embodiment it ispreferable that the resin film 6 have a thickness, T6, of 0.2 mm or moreand 1.0 mm or less. If the thickness T6 of the resin film 6 is 0.2 mm ormore, a sufficient strength of the liquid crystal panel can be ensuredeven if the glass substrate 101 of the TFT substrate and the glasssubstrate 201 of the counter electrode 2 are each made as thin as 0.5 mmor less. Therefore, in the liquid crystal display panel of the firstembodiment, a sufficient strength can be ensured even if the total panelthickness, TP, is 2 mm or less. In the liquid crystal display panel ofthis embodiment it is preferable that the total panel thickness TP benot larger than 2 mm and the panel thickness, TP-T6, exclusive of theresin film be not larger than 1.3 mm.

Since the resin film 6 exhibits a function as a reinforcing member forthe liquid crystal display panel, for example, as shown in FIG. 3A, thethickness T2 of the glass substrate 201 of the counter substrate 2 withthe resin film 6 affixed thereto can be made thinner than the thicknessT1 of the glass substrate 101 of the TFT substrate 1. Consequently, thetotal panel thickness TP can be further reduced.

In the case where the driving method for the liquid crystal displaypanel is of a lateral electric field type called IPS (In PlaneSwitching), for example, a conductor film 203 for the prevention ofelectric charging may be provided on a back surface of the glasssubstrate 201 of the counter substrate 2, in other words, on the surfaceto which the upper polarizing plate 5 is affixed, as shown in FIG. 3B.In this case, the back surface of the glass substrate 201 in the countersubstrate 2 cannot be subjected to polishing for the reduction ofthickness. When the conductor film 203 is thus formed on the countersubstrate, as shown in FIG. 3B, a back surface of the glass substrate101 in the TFT substrate, in other words, the surface to which the lowerpolarizing plate 4 is affixed, is ground to make the thickness T1 of theglass substrate 101 in the TFT substrate 1 smaller than the thickness T2of the glass substrate 201 in the counter substrate 2, whereby the totalpanel thickness TP can be reduced.

Further, it is preferable that the surface hardness of the resin film 6be harder than that of the upper polarizing plate 5. More specifically,it is preferable for the resin film 6 to have a surface pencil hardnessof 3 H or harder. The surface pencil hardness is meant a hardness withwhich the material surface is damaged when a line is drawn on thematerial surface with a pencil. That is, the surface pencil hardness of3 H means that the material surface is not damaged when a line is drawnon the resin film 6 with a pencil having a hardness of 3 H or softer.

To make the resin film 6 with a surface pencil hardness of 3 H orharder, there may be used a film obtained by forming a material having apencil hardness of 3 H or harder into a film shape, or there may beadopted a method wherein a material having an arbitrary pencil hardnessis formed into a film and then the surface of the film is subjected to ahard coating treatment so as to give a surface pencil hardness of 3 H orharder. In the case of using an acrylic resin or epoxy resin as thematerial of the resin film 6, the resin surface is subjected to a hardcoating treatment as in the latter method just referred to above to givea surface pencil hardness of 3 H or harder.

FIGS. 4 to 7 are schematic diagrams for explaining an example andfunctional effects of a hand-held electronic device for which the use ofthe liquid crystal display panel of the first embodiment is preferred.

FIG. 4 is a schematic front view showing a schematic configuration of adisplay unit of a conventional mobile telephone terminal, FIG. 5 is asectional view taken along the line B-B′ of FIG. 4, FIG. 6 is aschematic front view showing a schematic configuration of a display unitof a mobile telephone terminal using the liquid crystal display panel ofthe first embodiment, and FIG. 7 is a sectional view taken along theline C-C′ of FIG. 6.

The liquid crystal display panel of the first embodiment is a displaypanel which is preferably applied to a display of a hand-held electronicdevice such as, for example, a mobile telephone terminal.

The liquid crystal display used in the display unit of the mobiletelephone terminal includes, in addition to the liquid crystal displaypanel, a data driver which outputs a video signal to a video signal line(drain line) in the liquid crystal display panel, a gate driver whichoutputs a scanning signal to a scanning signal line (gate line) in theliquid crystal display panel, and a timing controller for controllingthe timing at which the video signal and the scanning signal are to beoutputted. In the case of a transmission type or semi-transmission typeliquid crystal display, the liquid crystal display has a back light(light source). These parts are held integrally by a frame member calleda display mold for example.

A liquid crystal display panel used in a conventional mobile telephoneterminal includes, for example as shown in FIGS. 4 and 5, a TFTsubstrate 1, a counter substrate 2, a lower polarizing plate 4, an upperpolarizing plate 5, and a sealing member 7. When the liquid crystaldisplay panel is seen by the observer, the upper polarizing plate 5,counter substrate 2, liquid crystal material 3, TFT substrate 1 andlower polarizing plate 4 are disposed in this order from the observer.If the liquid crystal display concerned is a transmission type display,a back light 8 is disposed further behind the lower polarizing plate 4when seen from the observer side. The liquid crystal display panel andthe back light 8 are held by a concave display mold 9 so that a backsurface side of the back light 8 is a bottom surface.

Such a liquid crystal display is accommodated within a sheath (case) 10having an opening of the mobile telephone terminal so that a displayarea DA of the liquid crystal display panel can be seen. In theconventional mobile telephone terminal, a transparent protective cover11 constituted by an acrylic plate or the like is usually disposed at aposition closer to the observer compared with the liquid crystal displaypanel. In many cases, the protective cover 11 is fitted in a depressionformed in the surface of the sheath 10 and is affixed to the sheath 10through a pressure-sensitive adhesive 12. For example, the protectivecover 11 functions to prevent the surface (upper polarizing plate 5) ofthe liquid crystal display panel from being damaged or prevent theliquid crystal display panel from being cracked upon exertion ofpressure on the liquid crystal display panel.

In the conventional mobile telephone terminal using the liquid crystaldisplay, it is necessary to use the protective cover 11 for protectingthe liquid crystal display panel. Thus, the thickness of the displayunit is increased.

On the other hand, in the liquid crystal display panel of the firstembodiment, the resin film 6 is affixed to the upper polarizing plate 5to enhance the strength of the liquid crystal display panel, and theresin film 6 with a surface pencil hardness of 3 H or harder makes itdifficult to damage the surface of the resin film 6. That is, in theliquid crystal display panel of the first embodiment, the resin film 6is endowed with the function of the conventional protective cover 11.Therefore, for example as shown in FIGS. 6 and 7, if the liquid crystaldisplay wherein the liquid crystal display panel is disposed so that theresin film 6 is positioned closest to the observer is accommodatedinside the sheath 10 of the liquid crystal display, the liquid crystaldisplay panel can be protected from being damaged and cracked due topressure even in the absence of the protective cover 11. As a result,the display unit of the mobile telephone terminal can be made thinnerthan the conventional counterpart.

In the display unit of the conventional mobile telephone terminal thereis an air layer between the liquid crystal display panel and theprotective cover 11, but the air layer can be eliminated by using theliquid crystal display panel of the first embodiment. Consequently, thedisplay efficiency can also be improved over conventional displays.

In the liquid crystal display panel of the first embodiment, the TFTsubstrate and the counter substrate 2 can be fabricated using glasssubstrates 101 and 201. Therefore, the multiple wiring layers 102 and202 can be formed more easily than in the liquid crystal display panelusing plastic substrates which is described in Patent Document 1.Besides, by forming the TFT substrate 1 and the counter substrate 2 withuse of the glass substrates 101 and 201, it is also possible to preventthe occurrence of unevenness in display caused by a change inenvironment.

FIGS. 8A and 8B is schematic sectional views showing modifiedconfigurations of the display unit of the mobile telephone terminalusing the liquid crystal display panel of the first embodiment. In FIG.8, as such modified configurations, there are shown two sectional viewswhich are FIG. 8A and FIG. 8B. These two sectional views correspond tothe sectional configuration taken along the line C-C′ of FIG. 6.

When the liquid crystal display having the liquid crystal panel of thefirst embodiment is applied to a mobile telephone terminal, it is notnecessary to affix the protective cover 11 to the surface of the sheath10, as shown in FIG. 7. However, when the liquid crystal display isaccommodated in such a state as shown in FIG. 7, water or the like isapt to get into the inside of the sheath through a gap formed between anouter periphery 10A of the opening area of the sheath 10 and the liquidcrystal display panel (resin film 6). As a result, wiring formed on theTFT substrate 1 of the liquid crystal display panel and wiring formed onanother circuit board are apt to be corroded.

Therefore, in the case of using the liquid crystal display panel of thefirst embodiment, for example as shown in FIG. 8A, it is preferable thatthe outline of both upper polarizing plate 5 and resin film 6 affixed tothe counter substrate 2 be made smaller than that of the lowerpolarizing plate 4 and that the counter substrate 2 and the sheath 10 befixed together by bonding with use of a pressure-sensitive adhesive 13.In this case, if the pressure-sensitive adhesive 13 is formed in anannular shape which surrounds the upper polarizing plate 5 and the resinfilm 6, the pressure-sensitive adhesive 13 serves as a wall and it ispossible to prevent the entry of water or the like into the inside ofthe sheath. Of course, an adhesive may be used instead of thepressure-sensitive adhesive 13.

For example as shown in FIG. 8B, if a projecting portion projectingtoward the counter substrate 2 is formed on the outer periphery 10A ofthe opening area of the sheath 10, the effect of preventing the entry ofwater or the line to the inside of the sheath is further enhanced.

FIG. 9 is a schematic front view for explaining an application of theliquid crystal display panel of the first embodiment and FIG. 10 is asectional view taken along the line D-D′ of FIG. 9.

In the liquid crystal display panel of the first embodiment, bothreduction in thickness of the panel and ensuring of a sufficientstrength thereof are attained by affixing the resin film 6 to the upperpolarizing plate 5 affixed to the counter substrate 2. Further, by usingsuch a liquid crystal display panel it is made possible to reduce thethickness of a hand-held electronic device such as a mobile telephoneterminal.

However, in the case where the outer periphery of the upper polarizingplate 5 and that of the resin film 6 are coincident with each other whenseen from the front side for example as is the case with the liquidcrystal display panel shown in FIGS. 1 and 2, the outer periphery endface of the upper polarizing plate 5 comes into contact with the outsideair for example as shown in FIG. 7 and FIGS. 8A and 8B. Consequently,the upper polarizing plate 5 is corroded and deteriorated due tomoisture contained in the outside air and there is a possibility thatthe upper polarizing plate 5 may be peeled off from the countersubstrate 2 or unevenness in display may result.

The occurrence of such a problem can be prevented by diminishing theoutline of the resin film 6 so that the outer periphery of the resinfilm 6 lies inside the outer periphery of the upper polarizing plate 5when the liquid crystal display panel is viewed from the front side forexample as shown in FIGS. 9 and 10. Of course, the outline of the resinfilm 6 should be diminished in such a manner that the outer peripherythereof lies outside the display area DA.

FIGS. 11A to 11C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel shown in FIGS. 9 and 10. In FIG. 11, thereare shown three sectional views 11A, 11B and 11C as structural examples,which sectional views correspond to the sectional configuration takenalong the line C-C′ of FIG. 6.

Also in the case where the liquid crystal display having the liquidcrystal display panel shown in FIGS. 9 and 10 is applied to a mobiletelephone terminal, it is not necessary to affix the protective cover 11to the surface of the sheath 10 for example as shown in FIG. 11A.Consequently, the display unit of the mobile telephone terminal can bemade thinner than the conventional counterpart.

Besides, since the outer periphery of the resin film 6 in the liquidcrystal display panel lies inside the outer periphery of the upperpolarizing plate 5, the outer periphery 10A of the opening area of thesheath 10 can be positioned inside the outer periphery of the upperpolarizing plate 5. Therefore, for example in comparison with the caseof FIG. 7, the path from the outside of the sheath 10 up to a side faceof the outer periphery of the upper polarizing plate 5 becomes long andcomplicated and the entry of moisture, etc. becomes difficult. As aresult, the side face of the outer periphery of the upper polarizingplate 5 becomes difficult to be corroded and deteriorated and it ispossible to diminish the possibility of the upper polarizing plate 5being peeled off from the counter substrate 2 or causing unevenness indisplay.

For example as shown in FIG. 11B, it is preferable that the upperpolarizing plate 5 and the sheath 10 be bonded and fixed together usinga pressure-sensitive adhesive 13. In this case, if the shape of thepressure-sensitive adhesive 13 is made an annular shape which surroundsthe resin film 6, the pressure-sensitive adhesive 13 serves as a walland it is thereby possible to prevent the entry of moisture, etc. intoinside of the sheath. As a result, the side face of the outer peripheryof the upper polarizing plate 5 becomes more difficult to bedeteriorated and it is possible to further diminish the possibility ofthe upper polarizing plate 5 being peeled off from the counter substrate2 or causing unevenness in display.

Moreover, for example as shown in FIG. 11C, if the outer periphery 10Aof the opening area of the sheath 10 is formed with a projecting portionprojecting toward the upper polarizing plate 5, the effect of preventingthe entry of moisture, etc. into the inside of the sheath is moreenhanced.

According to the liquid crystal display panel of the first embodiment,as set forth above, a required strength of the liquid crystal displaypanel can be ensured by affixing the resin film 6 in contact with theupper polarizing plate 5. As a result, the thickness of the glasssubstrate 10 in the TFT substrate 1 and that of the glass substrate 201in the counter substrate 2 can be reduced by polishing. Consequently, itis possible to reduce the thickness of the liquid crystal display panel.That is, in the liquid crystal display panel of the first embodiment itis possible to attain both reduction of thickness and ensuring of asufficient strength.

Further, since the TFT substrate 1 and the counter substrate 2 can eachbe formed using a glass substrate, there is little difference in theamount of deformation caused by an environmental change. Therefore, itis also possible to prevent the occurrence of unevenness in displaycaused by an environmental change.

Additionally, by applying the liquid crystal display (module) having theliquid crystal display panel of the first embodiment to a hand-heldelectronic device such as a mobile telephone terminal it is possible toreduce the thickness of a display unit of the hand-held electronicdevice.

In the first embodiment, a reference is made to an example in which thesurface pencil hardness of the resin film 6 is set to 3 H or harder,whereby for example the use of the conventional protective cover 11 ismade unnecessary when installing the liquid crystal display into themobile telephone terminal and the thickness of the display unit isthereby reduced. However, the application of the liquid crystal displaypanel of the first embodiment is not limited to such an example. Forexample, it goes without saying that the liquid crystal display panel ofthe first embodiment may be installed into a mobile telephone terminalusing the protective cover 11. In the case of using the protective cover11, the surface pencil hardness of the resin film 6 may be 3 H orsofter. In this case, however, it is preferable the total thickness TPof the liquid crystal display panel including the resin film 6 be set toa value of 1.3 mm or less.

Second Embodiment

FIG. 12 is a schematic sectional view showing a schematic configurationof a liquid crystal display panel according to a second embodiment ofthe present invention. The sectional view of FIG. 12 corresponds to thesectional configuration taken along the line A-A′ of FIG. 1.

The liquid crystal display panel of the second embodiment is basicallyof the same configuration as the liquid crystal display panel of thefirst embodiment. In the second embodiment, therefore, a descriptionwill be given below about only the difference from the first embodiment.

For example as shown in FIG. 12, the liquid crystal display panel of thesecond embodiment includes a TFT substrate 1, a counter substrate 2, aliquid crystal material 3 held between the TFT substrate 1 and thecounter substrate 2, a pair of polarizing plates (a lower polarizingplate 4 and an upper polarizing plate 5) disposed between the TFTsubstrate 1 and the counter substrate 2 both holding the liquid crystalmaterial 3, and a resin film 6 disposed on the counter substrate 2 side.

Also in the liquid crystal display panel of the second embodiment,though not shown, a phase difference plate may be disposed between aglass substrate 101 in the TFT substrate 1 and the lower polarizingplate 4 and also between a glass substrate 201 in the counter substrate2 and the upper polarizing plate 5.

In this case, unlike the first embodiment, the resin film 6 is disposedbetween the counter substrate 2 and the upper polarizing plate 5. Forexample, the resin film 6 is affixed in contact with the glass substrate201 in the counter substrate 2 through a pressure-sensitive adhesive orthe like. Further, the upper polarizing plate 5 is affixed in contactwith the resin film 6 through a pressure-sensitive adhesive for example.

Also in the liquid crystal display panel of the second embodiment it ispreferable that a film of a high light transmittance, especially acolorless, transparent film, be used as the resin film 6. In the liquidcrystal panel of the second embodiment the resin film 6 is disposedbetween the upper polarizing plate 5 and the counter substrate 2 (lowerpolarizing plate 4). Therefore, it is preferable for the resin film 6 tobe low, more preferably nearly zero, in optical anisotropy. Therefore,it is preferable to use an epoxy resin as the material of the resin film6. However, in the case where the optical anisotropy is of an allowablemagnitude or can be compensated, an acrylic resin for example may beused as the material of the resin film 6.

In the liquid crystal display panel of the second embodiment, the upperpolarizing plate 5 is disposed on the observer side (front side) withrespect to the resin film 6. Therefore, in the second embodiment, unlikethe first embodiment, it is not necessary to set the surface pencilhardness of the resin film 6 to 3 H or harder. Instead, in the liquidcrystal display panel of the second embodiment, the surface pencilhardness of the upper polarizing plate 5 positioned closest to theobserver is made 3 H or harder. This can be done for example by applyinga hard coating treatment to the surface of a conventional polarizingplate.

Also in the liquid crystal display panel of the second embodiment it ispreferable that the thickness T6 of the resin film 6 be set to a valueof 0.2 mm or more and 1.0 mm or less. If the thickness T6 of the resinfilm 6 is not smaller than 0.2 mm, it is possible to ensure a sufficientstrength of the liquid crystal display panel even if the glass substrate101 in the TFT substrate 1 and the glass substrate 201 in the countersubstrate 2 are made as thin as 0.5 mm or less. In the liquid crystaldisplay panel of the second embodiment, therefore, it is possible toensure a sufficient strength even if the total panel thickness TP ismade 2 mm or less. In the liquid crystal display panel of the secondembodiment it is preferable that the total panel thickness TP be 2 mm orless and that the panel thickness TP-T6 exclusive of the resin film be1.3 mm or less.

The resin film 6 also functions as a reinforcing member for the liquidcrystal display panel and therefore, as in the configuration shown inFIG. 3A, the thickness T2 of the glass substrate 201 in the countersubstrate 2 with the resin film 6 affixed thereto can be made smallerthan the thickness T1 of the glass substrate 101 in the TFT substrate 1.Consequently, the total panel thickness TP can be further reduced.

When the liquid crystal display panel is of the lateral electric fielddriving type called IPS, for example as in the configuration shown inFIG. 3B, there sometimes is a case where a conductor film 203 for theprevention of electric charging is provided on the back surface of theglass substrate 201 in the counter substrate 2, in other words, thesurface with the upper polarizing plate 5 affixed thereto. In this case,the glass substrate 201 in the counter substrate 2 cannot be subjectedto polishing for the reduction of thickness. Therefore, when theconductor film 203 is provided on the counter substrate 2, for exampleas in the configuration shown in FIG. 3B, the back surface of the glasssubstrate 101 in the TFT substrate, in other words, the surface with thelower polarizing plate 4 affixed thereto, is subjected to polishing tomake the thickness T1 of the glass substrate 101 in the TFT substrate 1smaller than the thickness T2 of the glass substrate 201 in the countersubstrate 2, whereby the total panel thickness TP can be reduced.

FIGS. 13A to 13C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel of the second embodiment. In FIG. 13 thereare shown three sectional views 13A, 13B and 13C as structural examples,which correspond to the sectional configuration taken along the lineC-C′ of FIG. 6.

Also in the case of applying the liquid crystal display having theliquid crystal display panel of the second embodiment to a mobiletelephone terminal, it is not necessary to affix the protective cover 11to the surface of a sheath 10 for example as shown in FIG. 13A.Consequently, the display unit of the mobile telephone terminal can bemade thinner than the conventional counterpart.

However, when the liquid crystal display is accommodated inside thesheath 10 in such a state as shown in FIG. 13A, moisture or the like isapt to get into the inside of the sheath 10 through a gap formed betweenan outer periphery 10A of the opening area of the sheath 10 and theliquid crystal display panel (upper polarizing plate 5), so that wiringformed in the TFT substrate 1 of the liquid crystal display panel andwiring formed in another circuit board are apt to be corroded.

Therefore, also in the case of using the liquid crystal display panel ofthe second embodiment, for example as shown in FIG. 13B, it ispreferable that the outline of the upper polarizing plate 5 and theresin film 6 both affixed to the counter substrate 2 be made smallerthan that of the lower polarizing plate 4 and that the counter substrate2 and the sheath be bonded and fixed together through apressure-sensitive adhesive 13. In this case, if the pressure-sensitiveadhesive 13 is formed in an annular shape which surrounds the upperpolarizing plate 5 and the resin film 6, the pressure-sensitive adhesive13 serves as a wall, whereby the entry of moisture, etc. into the insideof the sheath can be prevented.

Moreover, for example as shown in FIG. 13C, if the outer periphery 10Aof the opening area of the sheath 10 is formed with a projecting portionprojecting toward the counter substrate 2, the effect of preventing theentry of moisture, etc. into the inside of the sheath is furtherenhanced.

FIG. 14 is a schematic sectional view for explaining an application ofthe liquid crystal display panel of the second embodiment, whichcorresponds to the sectional configuration taken along the line D-D′ ofFIG. 9.

Also in the liquid crystal display panel of the second embodiment, theresin film 6 and the upper polarizing plate 5 are both affixed to theglass substrate 201 of the counter substrate 2, and the outline of theupper polarizing plate 5 may be made small so that the outer peripherythereof lies inside the outer periphery of the resin film 6, as shown inFIG. 14. In this case, it goes without saying that the outer peripheryof the upper polarizing plate 5 should lie outside the display area DA.

FIGS. 15A to 15C are schematic sectional views showing structuralexamples of a display unit of a mobile telephone terminal using theliquid crystal display panel shown in FIG. 14. In FIG. 15, there areshown three sectional views 15A, 15B and 15C as structural examples,which correspond to the sectional configuration taken along the lineC-C′ of FIG. 6.

Also in the case of applying the liquid crystal display using the liquidcrystal display panel shown in FIG. 14 to a mobile telephone terminal,for example as shown in FIG. 15A, it is not necessary to affix theprotective cover 11 to the surface of the sheath 10, whereby the displayunit of the mobile telephone terminal can be made thinner than theconventional counterpart.

Moreover, since the outer periphery of the upper polarizing plate 5 ofthe liquid crystal display panel lies inside the outer periphery of theresin film 6, the outer periphery 10A of the opening area of the sheath10 can be positioned inside the outer periphery of the resin film 6.Consequently, for example in comparison with the case of FIG. 13A, thepath from the outside of the sheath 10 to the inside thereof becomeslong and complicated, making the entry of moisture, etc. difficult.

In this case, it is preferable that the resin film and the sheath 10 bebonded and fixed together using the pressure-sensitive adhesive 13, forexample as shown in FIG. 15B. If the pressure-sensitive adhesive 13 isformed for example in an annular shape which surrounds the upperpolarizing plate, the pressure-sensitive adhesive 13 serves as a wall,whereby it is possible to prevent the entry of moisture, etc. into theinside of the sheath.

Further, for example as shown in FIG. 15C, if the outer periphery 10A ofthe opening area of the outer sheath 10 is formed with a projectingportion projecting toward the resin film 6, the effect of preventing theentry of moisture, etc. into the inside of the sheath is furtherenhanced.

According to the liquid crystal display panel of the second embodiment,since the resin film 6 is disposed between and in close contact with theglass substrate 101 in the TFT substrate 1 and the glass substrate 201in the counter substrate 2, it is possible to ensure a required strengthof the liquid crystal display panel. As a result, both glass substrates101 and 201 can be reduced in thickness by polishing and hence it ispossible to reduce the thickness of the liquid crystal display panel.That is, also in the liquid crystal display panel of the secondembodiment it is possible to attain both reduction of thickness andensuring of a sufficient strength.

Further, since the TFT substrate 1 and the counter substrate 2 can beformed using glass substrates, there is little difference in the amountof deformation caused by an environmental change. Consequently, it isalso possible to prevent the occurrence of unevenness in display causedby an environmental change.

Additionally, the display unit of a hand-held electronic device such asa mobile telephone terminal can be made thin by applying the liquidcrystal display (module) having the liquid crystal display panel of thesecond embodiment to the hand-held electronic device.

In the second embodiment reference is made to an example in which thesurface pencil hardness of the upper polarizing plate 5 is made 3 H orharder, thereby making the use of the conventional protective cover 11unnecessary when installing the liquid crystal display into the mobiletelephone terminal to attain the reduction in thickness of the displayunit. However, it goes without saying that the application of the liquidcrystal display panel of the second embodiment is not limited to thisexample, and the liquid crystal display panel may be installed into amobile telephone terminal using the protective cover 11. In the case ofusing the protective cover 11, the surface pencil hardness of the upperpolarizing plate 5 may be 3 H or softer. In this case, however, it ispreferable that the total thickness TP of the liquid crystal displaypanel including the resin film 6 be set to a value of 1.3 mm or less.

Third Embodiment

FIG. 16 is a schematic sectional view showing a schematic configurationof a liquid crystal display panel according to a third embodiment of thepresent invention.

The liquid crystal display panel of the third embodiment is basically ofthe same configuration as the liquid crystal display panel of the firstembodiment. In the third embodiment, therefore, a description will begiven only about points different from the first embodiment.

For example as shown in FIG. 16, the liquid crystal display panel of thethird embodiment includes a TFT substrate 1, a counter substrate 2, aliquid crystal material 3 held between the TFT substrate and the countersubstrate 2, a pair of polarizing plates (a lower polarizing plate 4 andan upper polarizing plate 5) disposed between the TFT substrate 1 andthe counter substrate 2 both holding the liquid crystal material 3, anda resin film 6 affixed in contact with the lower polarizing plate 4located on the TFT substrate 1 side.

That is, in the liquid crystal display panel of the third embodiment,unlike the first embodiment, the resin film 6 is disposed lies on theback surface side of the TFT substrate 1 and is most distant from theobserver. The resin film 6 is affixed in contact with the lowerpolarizing plate 4 with use of a pressure-sensitive adhesive forexample.

Also in the liquid crystal display panel of the third embodiment, thoughnot shown, a phase difference plate may be disposed between a glasssubstrate 101 in the TFT substrate and the lower polarizing plate 4 andalso between a glass substrate 201 of the counter substrate 2 and theupper polarizing plate 5.

Also in the liquid crystal display panel of the third embodiment it ispreferable that a film of a high light transmittance, especially acolorless, transparent film, be used as the resin film 6. For example,an acrylic resin or an epoxy resin may be used as the resin film 6.

In the liquid crystal display panel of the third embodiment, the lowerpolarizing plate 4 and the TFT substrate 1 are disposed more closely to(in front of) the observer with respect to the resin film 6. Therefore,also in the third embodiment, unlike the liquid crystal display panel ofthe first embodiment, it is not necessary to set the surface pencilhardness of the resin film 6 to 3 H or harder.

In the liquid crystal display panel of the third embodiment, forexample, it is preferable that the total of the thickness T1 of theglass substrate 101 in the TFT substrate 1 and the thickness T2 of theglass substrate 201 in the counter substrate 2 be 0.5 mm or less. Thethicknesses T1 and T2 of the glass substrates 101 and 201 may beapproximately equal to each other, or either one of them may be thin andthe other thick.

As a result, when a pressing force is exerted on the liquid crystaldisplay panel from the upper polarizing plate 5 side, the force can beborne by the resin film 6 affixed to the back surface of the liquidcrystal display panel. Therefore, even if the glass substrates 101 and201 are made thin, it is possible to ensure a sufficient strength of theliquid crystal display panel.

FIG. 17 is a schematic sectional view for explaining a modified exampleof the liquid crystal display panel of the third embodiment.

In the case of disposing the resin film 6 on the TFT substrate 1 side asin the third embodiment, the disposed position may be between the glasssubstrate 101 in the TFT substrate 1 and the lower polarizing plate 4 asin FIG. 17. In the case of disposing the resin film 6 between the TFTsubstrate 1 and the lower polarizing plate 4, it is preferable that theresin film 6 be low, more preferably nearly zero, in optical anisotropy.Therefore, it is preferable to use, for example, an epoxy resin as thematerial of the resin film 6. However, if the optical anisotropy is ofan allowable magnitude or can be compensated, for example an acrylicresin may be used as the material of the resin film 6.

Also in the liquid crystal display panel of the third embodiment it ispreferable that the thickness T6 of the resin film 6 be set to 0.2 mm ormore and 1.0 mm or less. If the thickness T6 of the resin film 6 is 0.2mm or more, a sufficient strength of the liquid crystal display panelcan be ensured even if the glass substrate 101 in the TFT substrate 1and the glass substrate 201 in the counter substrate 2 are each made asthin as 0.5 mm or less. Thus, in the liquid crystal display panel of thethird embodiment, a sufficient strength can be ensured even if the totalpanel thickness TP is set to 1.3 mm or less.

According to the liquid crystal display panel of the third embodiment,as set forth above, a required strength of the liquid crystal displaypanel can be ensured by disposing the resin film 6 in a contact manneron the back surface side of the lower polarizing plate 4 or between theglass substrate 101 in the TFT substrate 1 and the lower polarizingplate 4. Besides, since the required strength can be ensured by theresin film 6, the glass substrate 101 in the TFT substrate 1 and theglass substrate 201 in the counter substrate 2 can be reduced inthickness by polishing. Consequently, it is possible to reduce thethickness of the liquid crystal display panel. That is, also in theliquid crystal display panel of the third embodiment it is possible toattain both reduction of thickness and ensuring of a sufficientstrength.

Moreover, since the TFT substrate 1 and the counter substrate 2 can beformed using glass substrates, there is little difference in the amountof deformation caused by an environmental change. Therefore, it ispossible to prevent the occurrence of unevenness in display caused by anenvironmental change.

In the case of installing the liquid crystal display having the liquidcrystal display panel of the third embodiment to, for example, a mobiletelephone terminal, it is preferable, as in the conventional liquidcrystal display, that a protective cover for protecting the liquidcrystal display panel be affixed to a sheath 10 of the mobile telephoneterminal. However, in the liquid crystal display having the liquidcrystal display panel of the third embodiment, the total of thethickness T1 of the glass substrate 101 in the TFT substrate 1 and thethickness T2 of the glass substrate 201 in the counter substrate 2 is0.5 mm or less and the thickness of the resin film is 0.1 mm or more and0.3 mm or less. That is, in the liquid crystal display using the liquidcrystal display panel of the third embodiment, the liquid crystaldisplay panel is thinner than the conventional liquid crystal displaypanel and can be so much reduced in thickness. As a result, even if theprotective cover for protecting the liquid crystal display panel isaffixed to the sheath of the mobile telephone terminal, the display unitof the mobile telephone terminal can be made thinner than theconventional counterpart.

Although the present invention has been described concretely on thebasis of the above embodiments, it goes without saying that theinvention is not limited to the above embodiments, but that variouschanges may be made within the scope not departing from the gist of theinvention.

For example, in each of the above embodiments, reference is made to atransmission type or semi-transmission type liquid crystal display panelas an example, which has two polarizing plates, i.e., the lowerpolarizing plate 2 and the upper polarizing plate 5. However, thepresent invention is applicable not only to such a transmission orsemi-transmission type but also to a reflection type liquid crystaldisplay panel.

FIG. 18 is a schematic sectional view showing a schematic configurationwherein the present invention is applied to a reflection type liquidcrystal display panel.

For example as shown in FIG. 18, the reflection type liquid crystaldisplay panel includes a TFT substrate 1, a counter substrate 2, aliquid crystal material 3 held between the TFT substrate and the countersubstrate 2, and a polarizing plate 5 affixed to a glass substrate 201in the counter substrate 2. In the case of applying the configuration ofthe first embodiment to this display panel, there is provided a resinfilm 6 affixed in contact with the polarizing plate 5 which is disposedon the counter substrate 2 side.

When the display having such a liquid crystal display panel is viewedfrom the observer side, the counter substrate 2 is usually disposed onthe observer side with respect to the TFT substrate 1. That is, when theobserver looks at the liquid crystal display panel shown in FIG. 18, theresin film 6, polarizing plate 5, counter substrate 2, liquid crystalmaterial 3 and TFT substrate 1 are disposed in this order from theobserver side.

In this case, for example a reflective layer is formed in a multi-thinfilm layer 102 of the TFT substrate 1 and light incident on the liquidcrystal display panel from the resin film 6 side is reflected by thereflective layer in the multi-thin film layer 102 and is then emittedtoward the observer.

Even in such a reflection type liquid crystal display panel, by affixingthe resin film 6 formed of, for example, an acrylic resin or an epoxyresin to the polarizing plate 5 in a contact manner, it is possible toensure a sufficient strength even if the glass substrate 101 in the TFTsubstrate 1 and the glass substrate 201 in the counter substrate 2 arereduced in thickness by polishing. Thus, it is possible to attain bothreduction in thickness of the liquid crystal display panel and ensuringof a sufficient strength.

FIG. 18 shows an example in which the resin film 6 is disposed moreclosely to the observer compared with the polarizing plate 5 However,this configuration is not limited, and the resin film 6 may be affixedbetween the glass substrate 201 in the counter substrate 2 and thepolarizing plate 5 or to the back surface of the glass substrate 101 inthe TFT substrate 1.

Although in each of the above embodiments reference is made to anexample in which the present invention is applied to a liquid crystaldisplay panel, the present invention is applicable also to other displaypanels, e.g., a display panel in a self-light emission type displayusing organic EL (Electro Luminescence).

FIG. 19 is a schematic sectional view showing a schematic configurationin which the present invention is applied to an organic EL panel.

For example as shown in FIG. 19, the organic EL panel includes a TFTsubstrate 1, a counter substrate 2 (glass substrate 201), as well as aphase difference plate 15 and an upper polarizing plate 5 both affixedto the counter substrate 2. In the case of applying the configuration ofthe first embodiment to this panel, there is provided a resin film 6affixed in contact with the upper polarizing plate 5 which is disposedon the counter substrate 2 side.

In the organic EL panel, the upper polarizing plate 5 and a phasedifference plate 15 are combined together to form a circularlypolarizing plate, thereby preventing extraneous light from beingreflected (preventing extraneous light from entering an image displayarea in the display panel). For the phase difference plate 15, forexample, only a quarter-wave phase difference plate may be used, or botha quarter-wave phase difference plate and a half-wave phase differenceplate may be used in a stacked fashion. In particular, A combination ofthe upper polarizing plate 5 with a phase difference plate 15 having thequarter-wave phase difference plate and the half-wave phase differenceplate stacked makes it possible to form a wide-band circularlypolarizing plate.

In the organic EL panel, for example a light emitting layer using anorganic EL material is provided in the multi-thin film layer 102 of theTFT substrate 1 and the gradation of each pixel is controlled by turningON and OFF of the light emitting layer and by the luminance of light 14during turning ON of the light emitting layer. Therefore, the spaceenclosed with the TFT substrate 1, counter substrate 2 and sealingmember 7 is in a vacuum state. Further, unlike the liquid crystaldisplay panel, a multi-thin film layer 202 may be absent in the countersubstrate 2.

It goes without saying that the present invention is applicable not onlyto the liquid crystal display panel and the display panel using organicEL, but also to display panels similar in configuration to those panels.

1. A hand-held electronic device comprising: a liquid crystal displaydevice comprising a first substrate, a second substrate bonded to thefirst substrate, liquid crystal material held between the firstsubstrate and the second substrate, and an upper polarizing plateaffixed to the second substrate; a protective member disposed over theupper polarizing plate; and an adhesive member disposed between theprotective member and the upper polarizing plate and without an airlayer between the protective member and the upper polarizing plate;wherein the protective member is configured as a protective cover of thehand-held electronic device.
 2. A hand-held electronic device accordingto claim 1, wherein a surface pencil hardness of the protective memberis at least 3 H.
 3. A hand-held electronic device according to claim 1,wherein an upper surface of the second substrate is bonded to a sheathof the hand-held electronic device.
 4. A hand-held electronic deviceaccording to claim 2, wherein an upper surface of the upper polarizingplate is bonded to a sheath of the hand-held electronic device.
 5. Ahand-held electronic device according to claim 1, wherein a thickness ofthe second substrate is no greater than 0.5 mm.
 6. A hand-heldelectronic device according to claim 5, wherein a thickness of theprotective member is in a range of 0.2 mm to 1.0 mm.
 7. A hand-heldelectronic device according to claim 6, wherein a surface pencilhardness of the protective member is 3 H or harder.
 8. A hand-heldelectronic device according to claim 6, wherein an upper surface of thesecond substrate is bonded to a sheath of the hand-held electronicdevice.
 9. A hand-held electronic device according to claim 7, whereinan upper surface of the upper polarizing plate is bonded to a sheath ofthe hand-held electronic device.
 10. A hand-held electronic devicecomprising: a liquid crystal display device comprising a TFT substrate,a counter substrate bounded to the TFT substrate, and a polarizing platedisposed over the counter substrate. a protective member disposed overthe polarizing plate; and an adhesive member disposed between theprotective member and the polarizing plate and without an air layerbetween the protective member and the upper polarizing plate, whereinthe protective member is configured as a protective cover of thehand-held electronic device.
 11. A hand-held electronic device accordingto claim 10, wherein a thickness of the counter substrate is no greaterthan 0.5 mm.
 12. A hand-held electronic device according to claim 11,wherein a thickness of the protective member is in a range of 0.2 mm to1.0 mm.
 13. A hand-held electronic device according to claim 12, whereina surface pencil hardness of the protective member is 3 H or harder.